package com.qrpay.util;

import java.util.concurrent.atomic.AtomicInteger;

/**
 * 生成唯一键
 */
public final class NumberMaker {

    private NumberMaker() {
    }

    private static final AtomicInteger increment = new AtomicInteger();

    public static String createUniqueNo() {
        return System.currentTimeMillis() + "_" + String.format("%04d", increment.getAndIncrement());
    }
}